Almost from the time it was recognized as a genre, Free Music has faced longstanding complaints about its sound and volume. If you take the New Thing as an example, sounds are reputed to be too loud and frenetic. Conversely dealing with Europeanized Reductionism, the intonation is faulted as being too close to silence. Although these trombone-bass clarinet CDs arrive from either side of that equation, both create programs that can impress sophisticated listeners, regardless of volume

Auf den Punkt features two German improvisers with extensive experience: bass clarinetist Rudi Mahall, whose frequent playing partners include pianist Alexander von Schlippenbach and trumpeter Axel Dörner; and trombonist Christof Thewes, who is in bands with pianist Uwe Oberg and string-player Martin Schmidt. The CD’s 10 “Punkt” explorations are splintered, multiphonic and stentorian enough to suggest that the two use the German word punkt because it’s a near homonym to the English word punk, with all its implicit baggage. Exploration on the other hand, which is defined as the act or an instance of exploring, is a live set that can best be described as an exercise in micro-minimalism. Austrian trombonist Radu Malfatti has evolved this style over the past quarter-century, moving from Free Jazz that included his membership in blowing bands like The Brotherhood of Breath, to settle on advancing this measured nearly inaudible chamber improv. His partner here, Argentinean bass clarinetist Lucio Capece, moves between improvised and notated music, recording with the likes of tubaist Robin Hayward and trumpeter Birgit Ulher.

From the beginning Thewes’ and Mahall’s approach is Teutonic and upfront, layered and hard-hitting, but with some exquisite poetics hidden among the expositions. This lyricism is most obvious on tracks like “Punkt 10” and “Punkt 5”. On the latter, while Mahall’s slide-whistle peeps and mouth pops may be taken staccato, the tempo is moderato and used later on to color Thewes’ grace note exposition. As the daubs of brass and reed timbres run together the two lines move chromatically forward in polyharmonic swing. “Punkt 10” even ends with the reed man playing what could be a variant on “Mood Indigo”. Before that his contralto textures are matched with plunger harmonics from the trombonist, as Mahall too gradually descends to the chalumeau register. Nonetheless, while Thewes’ speedy, single-note snorts are somewhat atonal, it’s Mahall’s interjected reed bites which keep the broken octave concordance going without allowing the track to descend into obscurity.

When outlining the pseudo-canon that is “Punkt 9” the two get involved in contrapuntal breaks, as double-tonguing and concentrating trilling on Mahall’s part and roughened snorts and gurgles from Thewes come across as if they are updating a duet between Vic Dickinson and Edmond Hall. Appropriately smooth mid-way through, the clarinetist touches on pop-song-like variations as the trombonist’s plunger work provides the proper contrast. On “Punkt 4”, their repertoire of nearly identical note slurring plus breaths forced through the horns’ body tubes without fingering confirm their sonic cohesion. Nevertheless unexpected tongue slaps from Mahall and foreshortened slide motions from Thewes built around protracted silences link them to the Ur-reductionist work on Explorational.

As consecrated to frequent, elongated silences as Auf den Punkt is to a driving rainstorm of exaggerated broken tones, Capece and Malfatti arguably sound as few tones during Explorational entire session as Mahall and Thewes do on one short track. The underlying mood is of great calm, with the air only sporadically rent with instrumental sounds. Since the listener can’t see what actions the players are taking during this live session, one must rely on aural clues. Distant footfalls, faint buzzes, human respiration and undefined echoes add to the microscopic sound field. The air isn’t dead however, it’s just motionless, waiting for animation. When sound is noticeable, it takes place in split-second intervals and, more likely than not, can’t positively be ascribed to either trombone or bass clarinet.

With metallic resounding, sibilant tongue slaps or key percussion come into focus it’s the equivalent of a marching band crescendo in other circumstances. And very late in the narrative when there’s an extended, harmonized timbre involves both horns, it’s as if a symphony orchestra is playing fortissimo. Listen with almost canine hearing and a reed grace note complemented by a single brass tone can arise from the stasis. Completed by tongue popping, faint breathing and miniscule harmonized textures followed and separated by long stretches of silence is the sonic strategy. This isn’t passive ambient music, but a hushed overlay that aggressively demands committed listening.

Demonstrating the opposite ends of the Free Music spectrum from miniscule pianissimo to raucous fortissimo are the functions of both discs. While Mahall and Thewes audacious duet may be appreciated by all horn fanciers, truthfully the Capece-Malfatti performance may only attract dedicated micro-sound specialists.